Fuel feeding and distributing apparatus for internal - combustion engines



Nov. 18, 1952 H. KNUDSEN FUEL FEEDING AND DISTRIBUTING APPARATUS FOR INTERNAL-COMBUSTION ENGINES 7 Sheets-Sheet 1 Filed May 24, 1947 Hams I, [1 m sen, 9m,

,iwfwi 1952 H. KNUDSEN 5 FUEL FEEDING AND DISTRIBUTING APPARATUS FOR INTERNAL-COMBUSTION ENGINES 7 Sheets-Sheet 2 Filed May 24, 1947 Inuenfim Hans ljfnwciaem 'i -& ,4/M

mhm

H. 1.. KNUDSEN FUEL FEEDING AND DISTRIBUTING APPARATUS Nov. 18, 1952 FOR INTERNAL-COMBUSTION ENGINES 7 Sheets-Sheet 3 Filed May 24, 1947 IQNN NNN eefi [nz/enfor:

Ham/512A M66774 ww fl If); MM

m6 AW QQN m9 ww bh 9w H. KNUDSEN 2,618,252 FUEL. FEEDING DISTRIBUTING APPARATUS FOR INTERNAL-COMBUSTION ENGINES Nov. 18, 1952 7 Sheets-Sheet 4 Filed May 24, 1947 Nov. 18, 1952 H. L. KNUDSEN 2,618,252

FUEL FEEDING AND DISTRIBUTING APPARATUS FOR INTERNAL-COMBUSTION ENGINES Filed May 24, 1947 7 Sheets-Sheet 5 Ira/9722 57":- Hans Lfflmuiaem FUEL FEEDING AND DISTRIBUTING APPARATUS NOV. 18, 1952 KNUDSEN 2,618,252

FOR INTERNAL-COMBUSTION ENGINES Filed May 24, 1947 7 Sheets-Sheet 6 i 14. J50 in y /49 151 14. J42

ffaneL/Ynadsea Nov. 18, 1952 I KNUDSEN 2,618,252

FUEL FEEDING AND DISTRIBUTING APPARATUS FOR INTERNAL-COMBUSTION ENGINES Filed May 24, 1947 7 Sheets-Sheet 7 '[nuenZ 0r: fianalffnudsem .5 M

Ja M, 7

Patented Nov. 18, 1952 FUEL FEEDING AND DISTRIBUTING APPA- RATUS FOR INTERNAL COMBUSTION ENGINE S Hans L. Knudsen, Columbus, Ind., assignor to Cummins Engine Company, Inc., Columbus, Ind., a corporation of Indiana Application May 24, 1947, Serial No. 750,250

7 Claims.

My invention relates to fuel feeding and distributing apparatus for internal combustion engines and more particularly to devices of this character which are arrangedfor the handling of liquid fuel and its positive discharge in desired, equal quantities to a plurality of engine cylinders.

The present apparatus is of the same general type as that disclosed in United States Letters Patent No. 2,001,126, dated May 14, 1935, as regards the association of an injector for engine cylinders for forcibly delivering measured quantitles of fuel thereto, a fuel or metering pump common to all injectors, and a charging pump for delivering the liquid fuel under pressure to the metering pump. Accordingly, the invention disclosed herein is characterized by the same operating advantages in respect of a positive, mechanical and so-called two-stage handling of the fuel, i. e., a feeding of measured and equal charges of the fuel at relatively low pressure to the several injectors by the fuel pump, and a delivery of these charges by the injectors into the engine cylinders against the much higher compression pressures obtainin therein.

The principal object of the present invention is to provide a fuel feeding and distributing apparatus for internal combustion engines in which metering of the fuel charges to the injector lines is controlled by a hydraulic isochronous governor throughout all or a portion of the working range of the engine.

A further object is to devise an apparatus of the character indicated wherein the hydraulic pressure for the governor is derived from the pressure in the fuel line leading to the metering D p- A further object is the provision of a compact and light metering and distributing apparatus in which all elements thereof, including the governor control, are contained within a single housing, thus providing a self-contained unit which may be mounted on the engine in a completely assembled condition.

These and further objects of my invention will be set forth in the following specification, reference being had to the accompanying drawings, and the novel means by which said objects are effectuated will be definitely pointed out in the claims,

In the drawings:

Figure l is a sectional elevation of my improved apparatus as taken along the line I! in Fig. 3, the throttle valve and governing mechanism being shown in the positions which they assume when the engine is slowing down or coming to a stop.

Fig. 2 is a fragmentary, sectional elevation of the distributing mechanism showing the registration of one of the several ports for connecting the fuel p p P st n o o e the njector lines.

Fig. 3 is a plan view of the apparatus, looking in the direction of the arrow 3 in Fig. 1.

Fig. 4 is a section taken along the line -4 in Fig. 1, showing a portion of the distributing mechanism.

Fig. 5 is a diagrammatic, sectional View showing the relation of the throttle valve and fuel pump piston when the engine is operating with a fully open, fully closed, or partially closed throttle.

Fig. 5a is a fragmentary, sectional View taken substantially on the line 5a5a of Fig. 1.

Fig. 6 is an enlarged, fragmentary sectional elevation of the apparatus, as viewed in Fig. 1, but showing the governor mechanism adjusted to insure a fully open throttle.

Fig. '7 is an enlarged section taken along the line 'l--'l in Fig. 1, showing the piston valve which controls the delivery of fuel under pressure to the fuel metering pump chamber.

Fig. 8 is a section along the line 83 in Fig. 7.

Fig. 9 is a section along the line 99 in Fig. 1, showing the mechanism for controlling the reciprocation of the fuel metering pump piston.

Fig. 10 is a diagrammatic, sectional View of the pump which withdraws fuel from the main fuel tank, the charging pump for establishing a fuel pressure in the line leading to the fuel metering pump, and the float or auxiliary fuel chamber, these parts being shown in displaced relation to more particularly illustrate their operative relation.

Fig. 11 is a schematic, sectional elevation of a modified type of governor control in which the governor assumes speed control of the engine at any throttle setting within the idle to full speed throttle positions and progressively lowers the top speed after the throttle moves toward idling position.

Fig. 12 is a fragmentary section, taken along the line I 2l 2 in Fig. 11.

Fig. 13 is a schematic, sectional elevation of a still further modified arrangement of the governor control in which provision is made for holding the governor speed control lever in any determined position within its range of movement.

Fig. 14 is a section along the line i l-l4 in Fig. 13 showing a suggested arrangement for maintaining the governor lever in adjusted position.

Fig. 15 is a further sectional elevation of a governor control having speed droop characteristics.

Fig. 16 is a diagrammatic view'of the complete fuel feeding apparatus disclosed herein. 7

Referring to the drawings and more particularly to Figs. 1 and 10, the numeral l0 designates my improved apparatus which is intendedfor use with a multi-cylinder, twoor four-cycle engine of the diesel type. In the present instance, a twelve-cylinder, four-cycle engine is shown to illustrate the invention. In general outline, the fuel is withdrawn from a main tank II by a gear pump I2 and discharged into an auxiliary fuel tank in the form of a float chamber 13. From this float chamber the fuel is pumped by a second gear pump l4, denoted as the charging pump, which places a predetermined, minimum pressure on the fuel and delivers it to a fuel metering pump I5 which, in turn, discharges the fuel in quantities, as measured and determined by a throttle valve hereinafter described, to a distributing and phasing mechanism I6 which controls the final delivery of the charges to the individual injector line I! leading to a characteristic injector (not shown) of the type described in United States Letters Patent No. 2,190,015.

Referring to Fig. 1, which illustrates the major structural features of my improved apparatus, the numeral I8 designates an enclosing housing having journaled in the lower portion thereof a combination cam and driving shaft l3, one end of which projects without the housing and has affixed thereto a driving member 20. It will be understood that the member 25 is so driven from the engine crankshaft (not shown) that the shaft [9 rotates at crankshaft speed when used with a four-cycle engine.

Within the housing, a bevel pinion 2| is secured to the shaft [9 and meshes with a bevel gear 22 that is fast on the lower end of a shaft 23 which extends upward through a wall 24 provided in the housing and at its upper end is secured to a, cam disk 25 that rides on the upper surface of a flanged bushing 25 within which the shaft 23 is journaled. The peripheral surface of the disk 25 is provided with twelve equi-spaced cam lobes 2'! for a purpose presently explained. The speed ratio between the pinion 2| and gear 22 is 2:1, so that the cam disk 25 makes one complete revolution during two revolutions of the cam shaft l9 and the engine crankshaft.

A driving lug 28 projects upward from the disk 25 and fits within a correspondingly shaped slot provided in a connector 29 whose upper end includes a slot 30 for receiving a driving lug 3! that projects. from a rotary disk 32 which constitutes the movable member of the distributing and phasing mechanism 16. Preferably, the driving lugs 28 and 3! are diametrically related with respect to the disks 25 and 32, respectively, and are arranged at right angles with respect to each other so that a universal-like connection is thereby established between the disks. The top surface of the disk 32 is flat and bears against a flat surface provided on the underside of a distributor head 33 that is securedto the housing l8. The coacting surfaces of the disk 32 and head 33 are maintained in contact by a helical spring 34 which encircles the connector 29, the lower end of the spring abuting against the cam disk 25 and the upper end against the underside of the distributor disk 32.

The distributor disk 32 is provided with a U- shaped, radial passage 35 whose inlet port 36 is coaxial with the disk 32 and is in constant registration with the delivery port 31 that terminates a passage 38 formed in the head 33. The delivery port 39 of the passage 35 is also located in the upper surface of the disk 32 and its radial distance from the axis of the disk is such that it registers in succession during the rotation of the disk 32 with outlet ports 40, each of which con- 4 stitutes a part of a delivery passage 4! that communicates with an injector line H.

The delivery passage 38 is continued as a passage 42 which is provided in the housing wall 24 and it terminates in a port 43 formed in a bushing 44 that is mounted in a bore in the wall 24. The port 43 constitutes an inlet port for the passage 42 and also a delivery port for the fuel pump chamber presently described.

A constant stroke, sleeve piston 45 is reciprocable in the bushing 44 and its lower end is provided with an annular flange 45 against which seats the lower end of a helical spring 4'! which encircles the piston, the upper end of the spring bearing against an annular flange provided on the bushing 44. The spring 41 constantly urges the piston 45 to its lowermost position and the relationship is so designed that its upper end 43 at its uppermost position is substantially flush with the lower edge of the. port 43. The position of the piston in Fig. 1 is the lowermost position. This position of the piston therefore coincides with the end of its delivery stroke, as hereinaf er described.

A metering slide valve 49, hereinafter termed the throttle valve, is reciprocable within an axial bore 50 provided in the piston 45 and also within a bushing 5| that is mounted in the wall 24. The upper end of the valve 43 projects above the bushing 5i and is formed with an enlarged head 52. A helical spring 53 encircles that portion of the valve which projects above the bushing 5|, the lower end of the spring abutting the bushing and the upper end the underside of the head 52. The spring 53 always tends to urge the throttle valve upward to the uppermost lim iting position illustrated in Fig. 1, which, as hereinafter described, corresponds to a closed throttle position.

Adjacent to the port 48, the valve 43 may be reduced in diameter as at 54' and one or more radially disposed, bleeding ports 55 are located in the reduced portion which communicates with an axial passage 55 whose lower end terminates with the lower end of the throttle valve and the upper end with a radially disposed port 51 which in all positions of the throttle valve lies above the top surface of the bushing 51. It will be understood that the piston 45 constitutes the piston of the fuel metering pump l5 and that the pump chamber is defined by the opposed ends of the piston 45 and bushing 5 I, and the adjacent surfaces of the bushing 44 and throttle valve 49.

Referring to Fig. 9, the piston 45 is reciprocated in timed relation to the engine crankshaft through the medium of a cam sleeve 58 which is secured to the shaft [9 and is provided with six equi-spaced cam lobes 59 which periodically contact a roller 65 that is mounted on an intermediate portion of a rock lever 6|. The lever 6| is pivotally mounted in the housing [8 and its free end engages the under surface of the piston head 46, it being understood that the spring 5! constantly maintains this head in contact with the indicated end of the rock lever 61. For a purpose presently explained, the lower end of the piston bore 50 terminates in a, port 62 located in the head 46, and this port serves the dual purpose of providing a by-pass for all or a portion of the fuel in the pump chamber during the delivery stroke of the piston 45 and of lubricating the under surface of the piston head to prevent undue friction with the end of the rock lever Bl.

The efiicient operation of internal combustion engines of the character for which the present apparatus is intended requires an accurate and controllable measuring of relatively minute charges of the liquid fuel, these charges varying from drop-like in size as a maximum to a fraction of a drop equivalent approximately to the size of a pinhead. It has been ascertained that accurate control of such small fuel charges can only be insured if the metering pump is supplied with fuel under pressure, and the instrumentality for accomplishing this purpose will now be described.

Referring to Figs. 1, 3 and 10, the fuel is withdrawn from a main tank ll through a pipe 93, which may be provided with a check valve 63 (Fig. 16), into the pump chamber 33 by a gear pump I2 which comprises a pair of meshing gears 65 and 66, the former of which is secured to the cam shaft I9 and the latter to an offset shaft 19 that may be appropriately journaled in the housing for the pumps [2 and Hi. The discharge from the pump 12 is delivered to a passage 61 and thence to a passage 68 leading into the float chamber [3 and which passage is controlled by a, needle valve 69 carried by a float it that is pivotally mounted within the chamber 13, the parts being so arranged that, when the chamber [3 is filled, the needle valve 69 denies further delivery into the chamber.

Fuel from the chamber i3 is withdrawn through a passage 1! and delivered into the pump chamber 72 by the charging pump M which comprises a pair of meshing gears 73 and M, the former of which is secured to the cam shaft 19 and the latter to the offset shaft se The pump M establishes a pressure on the fuel delivery passage 15, which is conducted by a suitable duct to a filter l5 (Fig. 16) and a surge chamber 13* (see Figs. 1, 3 and 16) and then to a delivery passage 15, and this passage delivers the oil to a passage 16 (see Figs. 1 and 8) that is provided in the body 24 and the delivery end of this passage registers with a group of parallel ducts that extend through the wall of a sleeve 13 mounted in the body 24. The group of ducts Ti is in alignment with a similar group 19 that is also located in the wall of the sleeve i3 and in opposite relation to the duct group 17. The duct group H in turn communicates with the passage 42.

Communication between the duct groups is controlled by a piston valve 89 that is reciprocable within the sleeve 18 and which also comprises a guide portion 81 that is separated from the piston valve by a neck 82 having a reduced diameter relative to that of the piston valve, so that, when the valve occupies the position illustrated in Figs. '7 and 8, fuel under pressure may flow directly to the chamber of the metering pump, but, when shifted toward the. left, as viewed in Fig. 8, the delivery ends of the ducts in the group H are completely masked. The piston guide portion 8! is provided with an outwardly extending stem 83 having a head 84 and contacting one side of this head is a helical spring 85 which encircles the stem 33 nd has its opposite end bearing against the adjacent end of the sleeve 18. The spring 35 always tends to urge the piston valve in a direction masking the ducts TI and 79. Movement of the valve in the opposite direction is effected by one arm of a lever 85 which constantly bears against the head t l, while the other arm is provided with a roller 8'! that bears against the periphery of the cam disk 25 and periodically against the lobes 2'] on this disk. The intermediate portion of the 6 lever 86 is pivoted on a shaft 88 whose ends may be appropriately journaled in the housing 18.

From the foregoing, it will be understood that, during two revolutions of the cam shaft [9, corresponding to two revolutions of the engine crank shaft and therefore a delivery of a fuel charge to each of the injector lines, the piston valve 30 is reciprocated twelve times by the cam lobes 21, the parts being so timed that, when the piston valve occupies the position shown in Figs. 7 and 8 with a consequent delivery of fuel under pressure to the chamber of the metering pump, the delivery port 39 in the distributor disk 32 is masked by a portion of the stationary distributor head 33 between a pair of successive ports 49. Conversely, during periods of delivery by the metering piston 45, the piston valve 89 will be moved to a position masking the duct groups 17 and 19 and the distributor port 39 will register with one of the distributor ports 39 in the stationary head 33.

Referring to Fig. 10, whenever a suflicient amount of fuel has been collected in the float chamber l3 to cause the needle valve 69 to close the passage 68, provision is made for by-passing the fuel within the gear pump l2 through a passage 89 which connects the inlet and discharge sides of the pump, and located in this passage at some convenient point is a spring actuated pressure control valve 99. A similar by-pass arrangement denoted generally by the numeral 5H may be provided in the charging pump M. The relation between the gear pump l2, the charging pump [4 and float chamber [3, as illustrated in Fig. 10, is substantially identical with that disclosed and claimed in United States Letters Patent No. 2,056,259, dated October 6, 1936, and the operation of this portion of the apparatus is such that the passages 42, 38 and 35 are continuously filled with fuel under pressure.

In the operation of the apparatus so far described, a predetermined pressure is maintained in the passage 32 by the charging pump, as permitted by the reciprocation of the piston valve 89. As already described, the supply of fuel under pressure into the passage 42 periodically occurs during times when the delivery port 39 of the distributing mechanism is masked by the stationary head 33 and also while the metering piston 45 is being retracted to its lowermost position illustrated in Fig. 1. During times when the piston valve 89 is masking the ducts ET and 19, the metering piston 55 expels a measured charge of fuel through the passages 53, d2, 38 and 35 to one of the injector lines ll. Since the metering piston 45 is characterized by a constant stroke. variation in the sizes of the fuel charges can only be effected by varying the position of the throttle valve 49 and three such relative positions of this valve and piston are diagrammatically illustrated in Fig. 5.

Referring to the last-noted figure, the intermediate view shows a relation of the indicated parts corresponding to that illustrated in Fig. 1, i. e., a fully closed throttle, whereas the lefthand view shows relative positions for a, fully open throttle and the right-hand View illustrates conditions of partially open throttle. The distance between the lines A and B is intended to represent diagrammatically the full stroke of the metering piston 45.

In the intermediate view in Fig. 5 it will be observed that the throttle valve 49 hasbeen moved to a position in which the bleeding ports 55 cannot be masked by the piston 43. Accordingly, during this stroke, fuel in the pumpcham-. ber will be by-passed through'the ports. '55" into the passage 56 and thus be drained through the piston bore 50' and port :1 to the bottom of the housing I8, since each injector line at some point is provided with one or more check valves (not shown) of the spring type and the pressure required to open such valveor valves is. substantially greater than that required to cause flow through the ports 55. Therefore, with the valve 49 in the position indicated, no fuel charges will be delivered to the injector lines and this position thus correspondstoa fully closed positionof the engine throttle.

In the left-hand View in Fig. 5, the throttlevalve 49 occupies its lowermost position, namely, one in which the ports 55 are completely masked by the piston 45' at the beginning of itsdelivery stroke, thus preventing by-passing of any fuel from the pump chamber into the passage 55 during the upstroke of the metering piston. So long as the throttle valve occupies this fully opened position, the piston delivers equal and measured charges of maximum size to the several injector lines.

In the right-hand view in Fig. 5, the throttle valve occupies a position in which the ports 55 are in an intermediate position between the limiting positions illustrated in the left-hand and intermediate views of the same figure. Therefore, as the piston 45 moves upward on its delivery stroke, some of the fuel in the pump chamber will be by-passed through the ports 55 until these ports have been completely masked by the moving piston. Thereafter, the amount of fuel remaining in the pump chamber above the annular shoulder 92 will be discharged into one of the several injector lines. This position of the valve 49 corresponds to a partially open position of the engine throttle. Variations in the amount of fuel discharged can, of course, be effected by positioning the throttle valve 49 between any of the limiting positions illustrated in the left-hand and intermediate views in Fig. 5 and, in all cases, when the ports 55 are occupying some intermediate position between the possibie limiting positions of these ports, the amount of fuel dis charged through the injector lines will be a function of the distance traveled by the piston after completely masking these ports. It will be understood, of course, that, due to the reduced valve portion 54, complete masking of the ports 55 can never occur until after the upper end of the metering piston passes the annular shoulder 92.

Position adjustments of the throttle valve 49 can be accomplished in a variety of ways, but, in the present instance, it is proposed to accomplish this result by a hydraulic, isochronous governing device wherein the hydraulic pressure is derived from the fuel pressure established by the charging pump. Four modifications of the' hydraulic governing mechanism will be presently described, and attention will first be directed to that illustrated in Figs. 1 and 6.

Referring to Figs. 1, 5a and 16, fuel under pressure for the governing device is delivered by the charging pump I4, after passing through the filter to a duct I10 leading to a pressure control or regulating valve indicated generally at I1I. The pressure of the fuel delivered by the gear pump I4, of course, varies over quite a wide range because of the variations in engine speed. Furthermore, minor fluctuations in pres! sure of the fuel occur because of the intermittent admission of fuel through the slide valve 80. It

& has. een. found; QWever; that th h dra lic overnor func io s. best; if; he u l s up ed there o under a c n ant pr s r Fo these reasons, the pressure control valve I1-I is provided.

In the embodimentherein shown, the pressure control valve I1-I comprises an, open end casing I12 formed integrally with the body 24. The ends of the casing I;'1;2 are closed by plugs I13, while fixedly mounted within the casing isv a sleeve I14. The casing- I12 and the sleeve I141 are provided with registering ducts I15, communicating with the duct I10. Within the sleeve I14 is a piston valve, I16 normally held at one end of the sleeve bya spring I11, a stop I being provided on the valve I16 adapted to abut the adjacent plug I113 to limit movement of the valve. in that direction. The valve I16 intermediate its ends has a reduced: portion IB-I normally aligned with duct I15 so that fuel may flow transversely across the interior of the sleeve I14 to one end of a U-shaped duct I02 provided in the casing I12 with corresponding openings through the sleeve I14. The other end of the duct I83 reeenters the sleeve I14 beyond the end of the valve I16 so that fuel may flow there.- from to the governor through a passage 93.

In operation of the pressure control I1I, when the fuel supplied through the duct I19 is at the desired pressure, such pressure acts equally in both directions on the valve I16 in the space about the reduced portion I8I. The pressure of the fuel, however, when it enters the space about the stop I80 acts against the spring I11, and the strength of the spring is such as to balance the effect of this pressure, when the pressure is that desired for operation of the governor. Should the pressure of the fuel delivered by the charging pump I4 exceed such desired pressure, the valve I16 will be forced to the left, as viewed in Fig. 5a, compressing the spring I11 and reducing the effective opening of the duct I15 into the space about the reduced portion I8I, thereby reducing the flow of fuel and the pressure existing in the passage 93. In practice, it is found that this construction provides a substantially constant pressure for the fuel delivered to the governor.

The passage 93 extends through the body wall 24 and through a bushing 94 that is mounted in the wall, the end of this passage being in constant communication with an annular chan-. nel 95 provided around the periphery of a sleeve 96 that is journaled in the bushing. The lower end of the sleeve carries a bevel gear 91 that meshes with a bevel pinion 98 fast on the cam shaft I9, thus providing for the rotation of the sleeve 96 at a fixed speed ratio to the cam shaft.

The channel 95 communicates through a plu-. rality of radial ports 99 with an axial bore I00 provided in the sleeve 96. The upper end of the sleeve 96 is flanged and pivotally mounted thereon is a plurality of weight members IOI, each of which is provided with an arm I02 that extends radially inward toward the axis of the sleeve. The inner ends of the arms I92 always bear against the lower race of a thrust bearing I03 that encircles the upper end of a piston valve I04 which i reciprocable within the sleeve bore I00, The upper race of the thrust bearing I03 rides against the under side of an enlarged head I05 formed on the piston valve I04. A saddle I05 is secured to the valve head I05 in partially enclosing relation to the thrust bearing I03 and is provided, with an annular ring I 01 9, that serves as a base for the lower end of a helical loading spring I08 whose upper end carries a cap I09. Variations in the compression of the spring I08 are accomplished by a governor lever H which is secured to a rock shaft III that is journaled in the housing I0. One arm of the lever H0 bears against the spring cap I09 while the other arm is located externally of the casing for actuation in any approved manner.

The piston valve I04 is provided with a pair of spaced valve heads H2 and H3 which sealingly fit the bore I00 and are connected by a neck I I4 having a diameter reduced relative to that of the bore so as to provide therewith an annular space I00 which, in all positions of the valve, is filled with fuel under pressure. The rotary sleeve 96 is provided with an annular channel H5 disposed above the channel 95 and communicating with the bore I00 by means of a plurality of radial ports I I6. A similar channel I I1 and similar ports I I8 are located in the sleeve 96 below the channel 95, the axial spacing of the ports H0 and H8 being equal to the spacing of the valve heads H2 and H3 for a purpose presently explained.

A neck H9, similar to the neck H4, connects the valve head I I2 with a plurality of circumferentially spaced axially extending guide ribs I2! that serve to uide the piston valve I04 during its reciprocating movement in the sleeve bore I00 and which are separated from each other by drain channels I for a purpose presently explained. Similar drain channels I22 alternately arranged with similar guide ribs I23 are formed at the lower end of the piston valve and these ribs are connected with the valve head I I3 by a neck I 24.

The channel I I1 is in constant communication by means of a passage I25 with the lower end of a cylinder bore I20 that is formed in the body wall 24. Similarly, the channel I I5 is in constant communication with the upper end of the same cylinder bore through a passage I27. Reciprocably mounted within the cylinder bore I26 is a piston I28 from the lower end of which projects a stop I29 that is intended to engage the lower end of the cylinder bore and from the upper end of the piston extends a stop sleeve I30 that surrounds the piston rod I3 I. The piston rod extends upward through a plug I32 and upward movement of the piston I28 is limited by engagement of the sleeve I30 with the lower end of this plug. The piston rod extends completely through the plug I32 for engagement with one arm of a rock lever I33 that is secured to a rock shaft I34 appropriately journaled in the housing wall. The other arm of the lever I33 bears against the upper end of the throttle valve 49. It will be understood that the length of the piston I28 is such in relation to the stops I29 and I30 that it never masks the delivery ends of the passages I25 and I21, the piston I28 being shown in its uppermost position in Fig. 6 and its lowermost position in Fig. 1.

In describing the operation of the governing mechanism just described, attention will first be directed to Fig. 1 of the drawings. In this figure, it will be noted that the governor lever H0 has been rocked in a clockwise direction to substantially remove all pressure from the governor spring I08 and thus permit theweight members IOI to move to their outermost position. This movement raises the piston valve I04 so that the valve heads H2 and H3 are located above'the sure will, therefore, becomeeiifect'ive' against the upper end of the piston I28 and will thus move the piston to its lowermost position, which is the closed throttle position. During this movement of the piston, fuel in the lower end of the cylinder l26 will be relieved through the passage I25, channel I I1 and ports I I8 and thence through the drain passages I22 to the passage I35 provided in the bevel gear 97, from which the fuel drips to the bottom of the apparatus housing.

If now it is desired to provide for a full throttle opening at some determined and governed engine speed, the governor lever H0 is rocked counterciockwise to load the spring I08 and the extent of this loading will depend upon the speed at which it is desired to govern the engine, This loading of the spring effects a downward movement of the piston valve I0l to substantially the position illustrated in Fig. 6, or one in which the valve heads H2 and H3 are located below the ports H6 and H8, respectively. Fuel under pres sure is then admitted to the lower end of the cylinder I26, thus driving the piston I20 to its upper limiting position as determined by the sleeve I30 and expelling the necessary amount of oil from the upper end of the cylinder I20 through the passage I27, port I I6, and drain passages I20. The upward movement of the piston I28 rocks the lever I33 and shifts the throttle valve 49 to the fully open position illustrated in Fig. 6.

Thereafter, forthe particular loading of the spring I00, the governor controls the speed of the engine. With an increase in engine speed, such as may be caused by a reduction in load, the piston valve may move upwardly to and including a position in which the valve heads I I2 and H3 completely mask the ports H6 and H0, respectively, without changing the position of the valve S9. A further reduction in engine speed would result in the valve 49 beginning to move upward from the position shown in Fig. 6. Therefore, as the engine may vary in speed at the governed setting, the piston valve will float endwise in the bore I00. Variations in engine speed may be readily effected by varying the loading on the spring I08 through the governor lever H0. Accordingly, the arrangement shown in Figs. 1 and 6 enables the speed of the engine to be adjusted as desired while still retaining isochronous governor control at each setting of the governor lever. My improved governing device possesses the characteristics of an isochronous governor, since the piston valve I04 always tends to seek a position in which valve heads H2 and H3 cover their respective ports H6 and H0. The slightest speed variation will apply pressure either on top or bottom of piston I28 according to whether there is an increase or decrease in engine speed and the tendency for piston I28, therefore, is to float in any position demanded by the engine load and at a constant engine speed since piston valve I04 always reverts to substantially the same position.

The starting of the engine is accomplished merely by rocking the governor lever to some position such as i illustrated in Fig. 6 in order to secure an opening of the throttle valve, while stopping of the engine is effected merely by shifting the governor lever to the position illustrated in Fig. 1. This lever movement removes the pressure from the governor spring I08 and thus permits the weight members IOI under the impulse of centrifugal force to lift the piston valve to the position illustrated in Fig. l. Thereupon, the piston I28 is moved downward to the position shown in the last-noted figure and the throttle 11 valve 49 is raised by the spring 53 to the closed throttle position.

It will be understood that, owing to the constant stroke of the piston I28. and the fixed relation of the arms of the lever I33, any upward movement of the piston I28 effects a. constant movement of the throttle valve 49 in an opening direction, but the capacity of the weightmembers IDI to move outward at any particular speed is controlled by the pressure exerted on these members by the compression of the spring I98. Accordingly a relatively high compression of the spring I98 will necessitate a higher engine speed to rock the weight members IOI outward than would a lighter loading of the spring. A governor of the foregoing type, is particularly useful for variable speed engines of divers applica-- tions. Drainage accumulation in the bottom of the housing I8 may be returned to the float chamber I3 through passages I62 and I63.

In Fig. 11 is illustrated a modified governor mechanism in which the governor exercises control at all throttle settings of the engine, in such a manner that the engine will maintain a constant speed at all throttle settings; but the speed will decrease as the throttle is moved towardclosing position, and vice versa.

To this end, a throttle control lever I35 is externally mounted on one end of a rock shaft:

I38. that is suitably journaled in the housing I8 and interiorly of the housing this shaft is pro.- vided with an eccentric I3] on which is journaled an intermediate portion of a rock lever I38. One arm of this lever bears against theupper end of the throttle valve 49 while the other arm bears againstthe upper end of the governor piston rod I3I. spaced from the eccentric I3]. is a cam I39. Preferably, the high point of the eccentric and cam are located. approximately 90v degrees apart. One arm, of aspeed control lever I49 rides on the periphery, of the cam I 39 and this lever is intermediately pivotedjona rock shaft I4I whose ends are journaled in the housing I8, while the other arm of the lever bears against the spring cap I119. The remaining portion of the governor mechanism for this modification and others presently described is the same as that illustrated in Figs. 1and6.

When the parts occupy the position illustrated in Fig. 11;, .it will be obvious that, since the arm of the lever I,48.is in, contact with the high point of the cam. I 39, the spring I98 will, be loaded to the maximum extent, so that the piston valve I94 and the, weightmembers I9] will occupy. the

positions generally as shown in Fig. 6 and the lever I38 will accordingly be rocked to open the throttle valve 49 to the maximum extent. The governing device-is then set to control the maximum speed of the engine, However, if the lever. I35 is rotated in a counterclockwise direction through an angle of approximately 90 degrees, the indicated arm of the lever I49 will then ride on the low point of the cam I39, thus diminishing the load on the spring I98 to a point corresponding with the idling. speed of the engine. This reduction in the compression of the spring I98 is accompanied for reasons already noted in connection with Figs. 1 and'6, by a movement of the piston I28 to its lowermost position and,

hence, a corresponding movement ofthe piston rod I 3| The upper end of thisrod acts as a fulcrum on which the lever I38 swings due to the action of the eccentric I31. It will be obvious, therefore, that this, rocking of the lever Also formed on the shaft I36 and axially 1 2 I38 efiects a corresponding change in position of the throttle valve 49. from that. which it occupied when the parts were in the several positions illustrated in Fig. 11. The amount of fuel dis charged by the metering pump will therefore vary with the positions assumed by' the: throttle lever I35 between the limiting positions in which the arm of the lever [40 rides on the high and low points of the cam I39. With thisv arrangement, therefore, it is possible to provide for throttle control of the engine between the maximum and idling speeds thereof; but, when eitherof these speeds are reached, as well as in inter mediate throttle positions, the governor steps: in. and takes predominant control. A construction of this type is desirable. under conditions. re quiring manual throttle control; as well as. governor control, between the maximum and 'mirlie mum speeds of the engines, such as for motortrucks and locomotives.

In Fig. 13 is illustrated a still further modifica-- tion of my improved governor device which is more particularly intended for generator drives: or other installations requiring constant speed.

A start-and-stop lever I42 is secured extern-ala ly of the housing I8 to a rock shaft I 435th at is; journaled in the wall of the housing, and interiorly of the latter an eccentric I 44. is secured tothe shaft. A lever I45 isjournaled' on theec centric, one arm ofithe lever bearing against the upper end of the throttle valve49 and the other lever arm; against the end of the, governor piston: rod I3I. A governor lever I48 is also mounted externally of the housing I8 to a rock shaft I4! which is journaled' in the housing, and within. thelatteran arm I418 issecured to-the shaft I41 for the purpose. of engaging the spring cap. I09.

In the relation of the parts shown in the figure, the governor lever I46 is rocked to a position. in which substantially nopressure is exerted against the governor spring. I108; thus, permitting the: governor piston I 2.8 to. occupy its lowermost-pa sition as heretofore explainedin. connection with the governing device illustrated in Figs. 1 and'6. The start.-and.---stopv lever. I421occupiesthe rocked position illustratedin the figure, or one in which. the lever I'4.5.has been rotated in acounterclocke wise direction sufficient to. enable the spring 53'. to retract the-throttle valve to a position. of: full. closure. This position corresponds to.the poSi.'- tion of the valve illustratedin Fig. 1, so thatthe engineis at rest.

With this modificatiomit is contemplated that.

the governor spring I982 will be loaded. to secure some controlled speed. of the engine anditothis: end provision is. made for holding the governor:

lever I4;6.in any desired position within its rangeof movement; For this purpose, a capscrew I49:

extends through the end Ofithfl governorlever and. through. an. arcuateslot I59: provided". in. a

quadrant: I51:- that; forms a part: of: the: housing- I8. A frictionwasher. l52;may;begripped against the.surface=of the. quadrant by meansi of. a nut- I53, it' being understood; that. thisv manner: of

securing the governorleverin. any; adjusted posi tion is intended to generically illustrateany conr. ventional means. for: accomplishing.- the indicated.-

purpose.

opening of the; throttle valve. 49..

extent, the engine will run at the required constant speed under the control of the governor. When it is desired to stop the engine, the throttle lever I42 is moved counterclockwise as illustrated in Fig. 13, thus causing the throttle valve 49 to move to its no fuel or stop position, the governor piston rod I3I acting as a fulcrum for lever I45.

In Fig. 15, there is illustrated a further modification of the governor mechanism which is also of the constant speed type, but arranged to provide for a speed droop so that this isochronous type of governor will function like an ordinary mechanical governor.

A start-and-stop lever I54 is mounted externally of the housing I8 on one end of a rock shaft I55, and within the housing there is secured to this shaft an eccentric I55. The intermediate portion of a lever I'I is journaled on the eccentric I56, one end of the lever engaging the upper end of the throttle valve 49, while the other lever arm contacts the end of the governor piston rod I3I. The arm of the lever I51 to the right of the shaft I55, as viewed in Fig. 15, is provided with an abutment I58 against which rests an arm of a speed droop lever I59 that is intermediately secured to a rock shaft I60 whose ends may be journaled in the housing I8. The other arm of the lever I59 bears against the spring cap I09.

With this modification, the engine may be started by rocking the lever I54 in a clockwise direction to the position shown in Fig. 15, and thus, through the eccentric I55, efiecting a corresponding rocking of the lever I51 and a movement of the throttle valve 49 in an opening direction. Stopping of the engine is accomplished by rocking the lever I54 in the opposite direction and, during this movement, the left-hand lever arm of the lever I51 pivots on the fulcrum provided by the upper end of the governor piston rod I3I.

With the parts in the position shown in the figure, the spring I08 is loaded to move the piston valve I04 to place the piston I28 in the uppermost position shown in Fig. 6, when the engine is turned over by the starter. When the engine starts and there is no load on the engine, the weight members IOI, as the speed increases, swing out, moving piston valve I04 towards top position and piston I28 toward bottom stop. If the load on the engine is increased, the speed of the engine decreases and the Weight members IOI swing inward sufficiently to shift the piston valve to substantially the position illustrated in Fig. 6, followed by an upward movement of the piston I28, together with its piston rod I3I. The foregoing action results in a rocking of the lever I5I in a clockwise direction and a further opening of the throttle valve 49, accompanied by, and due to the rocking of the lever I59 in a clock wise direction, a reduction in the compression of the spring I08, so that the governed speed decreases as the load increases, and vice versa. It is important in this arrangement that the torque exerted by spring 53 be stronger than that exerted by lever I59 and the governor spring I08 and that suificient hydraulic pressure be exerted against the governor piston I28 to overcome the resultant forces of the springs 53 and I08. An arrangement of the character illustrated in Fig. is particularly desirable in connection with the operation of alternators in parallel since it is possible to thereby provide a bet- 14 ter division of the load between the different units.

It may be particularly noted that it is possible with the, arrangement shown in Fig. 15 to provide for an increase in the governed speed of the engine with an increase in the load. This result may be accomplished by providing an abutment I5I, similar to the abutment I58 on that arm of the lever I51 which lies to the left of the shaft I55. With the arm of the speed droop lever I59 resting on the abutment I6I, it is obvious that, when the load on the engine is increased, the loading of the governor spring I08 will also be increased, because of the rocking of the lever I59 in a counterclockwise direction.

My improved apparatus renders it possible to incorporate with a fuel pump and distributing apparatus for a multicylinder internal combustion engine any one of the different forms of hydraulic isochronous governing controls hereinbefore described and to associate this control in a compact, built-in structure which also embodies the metering or fuel pump and distributing mechanism. It is contemplated that sudden movements of the governor piston I28 may be restrained by suitably proportioning the sizes of the passages I25 and I21, so that some restriction is exercized on the flow of fuel therethrough. The structure would then be characterized by a dashpot action in that the slow shifts of the piston would be freely permitted.

My improved governor control is particularly useful in installations where the critical or torsional speed of the engine is relatively close to the desired governed speed of the engine. This critical speed may be an intermediate speed within the range of engine speed, but, due to the delicate and responsive characteristics of the type of governor proposed herein, it is possible to operate close to and on either side of the critical speed of the engine.

I claim:

1. In a fuel feeding apparatus for a multi-cylinder internal combustion engine, a fuel metering pump for delivering metered quantities of fuel to the cylinders including an adjustable bleed valve for bleeding off fuel delivered by said pump, a source of fuel under pressure for supplying fuel to said pump, a hydraulic actuator operabl by fuel from said source for adjusting said. bleed valve, a valve for controlling the flow of fuel to said actuator, a governor adapted to be driven by the engine for operating said last-mentioned valve, said governor including weights adapted to swing outwardly on increase in engine speed and a spring resisting such outward movement, a lever connecting said actuator and said bleed valve, and a manually operable lever connected to said first-mentioned lever for manually shifting said bleed valve and having a connection for varying the resistance of said spring.

2. In a fuel feeding apparatus for a multicylinder internal combustion engine, a fuel metering pump for delivering metered quantities of fuel to the cylinders including an adjustable bleed valve for bleeding off fuel delivered by said pump, a source of fuel under pressure for supplying fuel to said pump, a hydraulic actuator operable by fuel from said source for adjusting said bleed valve, a valve for controlling the flow of fuel to said actuator, a governor adapted to be driven by the engine for operating said last-mentioned valve, said governor including weights adapted to swing outwardly on increase in engine speed and a spring resisting such outward movement, a lever connecting said actuator and said bleed valve, and a manually operable lever shiftable independently of said first-mentioned lever for varying the resistance of said spring;

3. In a fuel feeding apparatusfor'a multi-cylinder internal combustion engine, a fuel met ring pump for delivering metered quantities of fuel:

to the cylinders including an adjustable bleedvalve for'bleeding ofi fuel delivered by said pump,

asourc of fue1 under pressure for supplying fuel to-said pump, a hydraulic actuator operable by fuel from said source for adjusting said bleed valve, a valve for controlling the flow of fuel to said: actuator, agovernor adapted-to be driven by the engine for operating said last-mentioned valve, said governor including weights. adapted to swing outwardly on increase in engine speed and aspring resisting such. outward movement, a lever connecting said actuator and said bleedvalve, a manually operable lever connected to said first-mentioned'lever' for manually shifting said bleed valve, and a second manually operable lever for varying the resistance of said spring.

4. In a fuel feeding apparatus for a multicylinder internal combustion engine, anfuel meter-ing pump'for delivering metered quantities of fuel to the cylinders including an adjustable-bleed valve for bleeding off fuel-delivered by said pump, a source-of fuel under pressure forsupplying fuel tosaid pump, a hydraulieactuator operable by fuel from said source for adjusting said bleed valve, a valve for controlling the flow of'fuel to said actuator, a governor adapted to be driven by the engine for operating said last-mentioned valve; said governor including weightsadapted to swing outwardly onincrease in-engine speed'and-a spring resisting suchoutward movement, a lever connecting said actuator and said bleed valve, a

manually operable lever connected to'said first-- mentioned lever for manually shifting said bleed valve, a cam actuated by said manually operable lever, and a, lever operated by said cam for varyingthe resistance of said spring.

5. Inafuel feeding apparatus for a multi-cylinder internal combustion engine, a fuel metering pump for delivering metered quantities of fuel to. the cylinders including an adjustable bleedvalve for bleeding off fuel delivered by said pump,

a source offuel under pressure for supplying fuel to saidpump, a hydraulic actuator operable by fuel from said source for adjusting said bleed valve, avalve for controlling the flow'of fuel to said actuator, a governor adapted to be driven by'the engine for operating said last-mentioned valve, said governor including. weights adapted to swing outwardlyon increase in engine speed- 16 and a spring resisting 'suchoutward movement, a: lever connecting said actuator and said bleed valve, a lever actuated by said first-mentioned lever for varying the resistance ofsaid spring, and a manually operablelever connected tosa-idfirstmentioned leverfor manually shifting said bleedvalve;

6. In a fuel feeding apparatus for a multicylinder internal combustion engine, a fuel metering pump for delivering metered quantities of fuelto the cylinders including an adjustable bleed valve for bleeding off fuel delivered bysaid pump, a governor adapted to be driven by the engine including weights adapted to swing outwardly on increase in engine speed and a spring resisting such outward movement, a lever connected to said bleed valve andresponsive to the action of the-governor, and a manually operable lever connected to said first-mentioned lever for manually shifting said bleed valve and having a connection for varying the resistance ofsaid spring;

7-. Ina fuel feeding apparatus for a multicylinder internal combustion engine; a fuel metering pump for delivering metered quantities of fuel to the cylinders including an adjustable bleed valve'for bleeding oif fueldelivered by saidpump, a governor adapted to be-driven-by the'engine including weights adapted to swing outwardly on increase in engine speed and aspring resisting such outward movement, a lever connected to said bleed valve and responsivetothe-action ofthe governor, and a manually operablelever shiftable' independently of said first-mentioned lever for varying the resistaneeofsaid spring;

HANS L. KNUDSEN;

REFERENCES CITED The following references are ofreco'rd in the file of this patent:

UNITED STATESPATENTS 

